Preoperative functional connectivity and postoperative neuropathic pain in degenerative cervical myelopathy: An exploratory postoperative follow-up study using resting-state functional MRI.

INTRODUCTION

Neuropathic pain (NP) may persist after decompression surgery for degenerative cervical myelopathy (DCM). Although clinical factors associated with postoperative NP have been reported, neuroimaging correlates based on functional connectivity (FC) remain poorly understood.

RESEARCH QUESTION: Are specific preoperative resting-state FC patterns associated with postoperative NP status in patients with DCM?

MATERIAL AND

METHODS

In this retrospective observational study using prospectively collected data, we analyzed 34 patients who underwent cervical decompression surgery for DCM between 2020 and 2024. NP was assessed using the Spine painDETECT Questionnaire (SPDQ) preoperatively and 6 months postoperatively. Patients were classified into NP improvement group (n = 7) and non-improvement group (n = 27). Preoperative resting-state functional MRI data underwent whole-brain ROI-to-ROI FC analysis using the CONN toolbox. Between-group FC differences, correlations with patient-reported outcomes, and factors associated with postoperative SPDQ scores were evaluated.

RESULTS

Two preoperative FC networks showed significant between-group differences. FC1, between the right middle frontal gyrus and right thalamus, was higher in the NP improvement group (p-FDR = 0.034), whereas FC2, between the left temporal fusiform cortex and left occipital fusiform gyrus, was higher in the NP non-improvement group (p-FDR = 0.024). FC2 showed moderate correlations with changes in pain intensity, quality of life, and upper-limb function. Multivariable analysis identified FC1 as independently associated with postoperative SPDQ scores (β = -24.05, p = 0.001).

DISCUSSION AND

CONCLUSION

Distinct preoperative FC patterns were associated with postoperative NP status. Preoperative FC may provide exploratory neuroimaging correlates of postoperative NP, although further validation is warranted.